Hydraulic operated lid for canning retort



March 28, 1967 M. w. LOVELESS 3,311,255

HYDRAULIC OPERATED LID FOR CANNING RETORT Filed Dec. 17, 1964 2 Sheets-Sheet 1 1T INVENTOR.

I MARION W. LOVELESS ATTORNEYS N. LOVELES HYDRAULIC OPERP-LTED LID FOR CANNING BETOQT 2 Sheets-Sheet Filed Dec INVENTOR. MARION W. LOVELESS ATTORNEYS United States Patent 3,311,255 HYDRAULIC OPERATED LID FOR CANNING RETORT Marion W. Loveless, 419 S. Allegheny, Tulsa, Okla. 74112 Filed Dec. 17, 1964, Ser. No. 419,075 2 Claims. (Cl. 220-36) This invention relates to a canning retort. More particularly, this invention relates to a canning retort which includes a hydraulically controlled lid. Most particularly, this invention relates to a canning retort in which the sequential opening and closing operations of a hydraulically operated lid are automatic.

One of the most commonly used method of preserving food is by sealing the food in metal containers. In order to prevent bacterial decay, the food in the sealed container must be subjected to high temperatures, a process called sterilization. This process is also commonly referred to as canning. It can be readily understood that should the cans be heated to high temperatures while they are subject to ambient atmospheric pressure, they would burst because of the high pressures developed by the liquids sealed inside. To prevent this rupture, the heating or canning operation is carried out in a sealed retort in which the cans may be heated to any temperature in order to carry out the sterilization process without any danger of being ruptured, since the pressure inside and outside of the cans will be equal at all times.

The canning process is still largely a batch process involving a great deal of manual labor. A great deal of time and labor are involved in opening the retort, loading the retort, closing and sealing the retort, and subsequently opening and unloading the retort. This invention provides a means of speeding up and simplifying the opening and closing operations with the expenditure of a minimum amount of labor.

The primary object of this invention is to provide a canning retort which is designed with a lid which can be tightly sealed, and in which the lid can be opened and closed automatically.

Another object of this invention is to provide a canning retort in which the opening and closing of the lid is controlled by one switch which is strategically placed and easily accessible, so that a great saving in time and labor are realized.

A further object of this invention is to provide a canning retort in which the opening and closing of the lid are accomplished hydraulically, and in which the sealing and locking of the lid are maintained by hydraulic pressure.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

FIGURE 1 is a top elevational view of the canning retort showing the lid in closed position.

FIGURE 2 is a side elevational view of the canning retort with the lid in closed position.

FIGURE 3 shows a detail view of the lid locking cylinder and plunger assembly.

FIGURE 4 is a side elevational view of the canning retort with the retort rotated 90 counterclockwise from the position shown in FIGURE 2.

Referring now to the drawings in detail, the retort, generally 10, includes a body portion, generally 12, and a lid portion, generally 14. The body portion 12 is deice signed to include various passageways interiorly for the passage of steam and water, and also includes various plumbing connections to permit the body portion of the retort to be connected to exterior water and steam outlets as well as to the requisite drains.

It is understood that the retort is to be constructed of such material and of such design as to withstand the expected pressures. The body portion includes the supports 16 which may be fixed or movable, and which may be adapted to the canning operation of which this retort is to be a part. A lid, generally 14, fits closely onto the body portion 12, and, when the retort is in operation, the lid is locked into position and sealed by a pressure seal. The lid 14 is connected to the body portion 12 by means of the sliding hinge, generally 56, including the body hinge bracket 57, hinge pin 58, and sliding hinge bracket 69. The lid portion is further connected to the body portion by means of the upper swivel bearing 22 which connects the lid arm 28 to the lifting rod 26; the lifting arm 26 is slidably engaged with the lid lifting cylinder 24. Secured to the end of the lifting rod 26 inside the lid lifting cylinder 24 is a piston oriented axially with regard to cylinder 24. Opposite faces of the piston at the end of rod 26 can be acted upon alternately by hydraulic fluid flowing through the lines 66 into the cylinder 24 so that the rod 26 will move in response to the direction of the force applied to the piston in the cylinder 24. The rod is fitted with a seal to prevent the escape of hydraulic fluid.

A lid lifting cylinder 24 is attached to the body portion 12 by means of attachment of the lower cylinder bracket 19 to the lower bearing pin 21 which passes rotatably through the lower cylinder swivel bearing 20. The lower swivel bearing 26 is attached to the body portion by means of the cylinder support 18.

The lid 14, when closed, is locked into position by the operation of the lid locking cylinder 30. Also, prior to the opening of the lid 14, the lid locking cylinder 30 is activated in the reverse direction to unlock the lid. The operation of the cylinder 30 is dependent upon the direction of flow of the hydraulic fluid through the hydraulic lines 66 into cylinder 36 and the resultant force exerted by the hydraulic fluid upon either the front face or rear face of a piston located axially within cylinder 30 and secured to the end of the lid locking plunger 32. The plunger 32 is also fitted with a seal to prevent the escape of hydraulic fluid. The lid locking plunger 32 is in turn secured to the plunger sleeve 34 which is in turn secured to the guide pin 36. The guide pin 36 operates slidably within guide slot 40, and is kept from becoming disengaged from guide slot 40 by means of the attachment of guide pin washer 38. Guide pin 36 also operates loosely and rotatably within the flange opening 44 of flange 42 attached to the lid 14. The cylinder 30 rests upon the lid cylinder support 46, which at one end thereof is turned upwardly to form the attachment plate 48 to which the cylinder bearing 50 is attached. The cylinder 30 is attached to plate .8 and permitted to move arcuately by means of the cylinder connector 54 and the bearing pin 52.

When closed, the lid 14 can be rotated clockwise by the action of cylinder 36 to a position whereby the locking pins 64 are secured beneath a horizontal portion 63 of arm 62 and against the rear wall of the locking arms 62. The locking arms 62 are slightly beveled so that an additional sealing and locking force is applied to the lid 14. Conversely, the lid 14 is unlocked when the cylinder imparts a counterclockwise motion to the lid so that the locking pins 64 are clear of the locking flanges 62. As briefly mentioned above, the lifting cylinder 24 and the locking cylinder 30 are operated by hydraulic fluid. The hydraulic fluid operates against both faces of the pistons located inside the cylinder and attached to the ends of the rods 26 and 32. The pressure of the hydraulic fluid is developed by a pump and the hydraulic fluid is supplied to the pump by a hydraulic fluid reservoir; both the pump and the reservoir may be attached to, or in close proximity to, the canning retort or may be remote therefrom. The pump is, of course, driven by an electric motor. The direction of flow of the hydraulic fluid is controlled by solenoid valves the locking cylinder solenoid valve 63 controls the direction of the fluid supplied to the locking cylinder 30 and the lifting cylinder solenoid valve 70 controls the direction of the fluid supply to the lifting cylinder 24. The operation of the lid closing and locking mechanisms is controlled by the control switch 72 which is connected electrically to the motor which drives the pump and to the solenoid valves 68 and 70, and to the micromagnetic switch 74 which will be further described hereinafter.

If it is assumed that the lid is initially in a closed and locked position, the lid will be tightly sealed, all of the locking pins 64 will be held tightly against the locking flanges 62, and the sliding hinge bracket 60 which fits loosely around the sliding hinge pin 58 will be positioned toward the counterclockwisemost portion of the sliding hinge 56. When the lid is in this closed and locked position, the lid arm 28 is also in its clockwisemost position, and the lifting rod 26 and lid lifting cylinder 24 are consequently canted slightly in response to this position of the lid. The rod 26 and cylinder 24 are permitted to be canted because the arm 28 is connected to the rod 26 by means of the upper swivel bearing 22, and the cylinder 24 is connected to the cylinder support 18 by means of the connection of the lower cylinder bracket 19 through the lower cylinder swivel bearing 20. This lateral movement of the lid is permitted by reason of these swivel bearings and also by the allowance of suflicient space between the upper rod bracket 23 and the upper swivel bearing 22 as well as between the lower cylinder bracket 19 and the lower cylinder swivel bearing 20.

The control switch 72 has two buttons marked open and close. Pressing of the open button initiates the unlocking and opening operations. Since the switch is connected to the pump, the pump starts operating immediately. The solenoid valves 68 and 70 include time delay electronic elements which control the valves in response to the operation of the electrical switch and pump. After a short delay which permits the pump to build up pressure, the locking cylinder solenoid valve 68 is operated in the manner which permits the hydraulic fluid to flow through the lines 66 to the cylinder 30 and against the face of the piston contained therein. The pressure exerted against the face of the piston is transmitted to the plunger 32 and the sleeve 34, The guide pin 36 fits loosely through the sleeve 34 so that the pin may rotate freely. As the plunger and sleeve move tangentially counterclockwise with respect to the lid 14, the guide pin 36 slides along the guide slot 40 toward that end of the slot which is remote from the cylinder 30. The plunger sleeve 34 and the guide pin washer 38 arranged on either side of the cylinder support 46 insure that the guide pin does not slip from the slot 40. The motion of the guide pin is transmitted to the lid through the flange 42 which fits loosely and unattacha'bly over the guide pin 36. As the lid rotates in a counterclockwise direction, the cylinder 24 and rod 26 approach a position such that a plane drawn through these two elements would be substantially vertical. At the same time, the one sliding hinge bracket 60 approaches the micromagnetic switch 74 and activates this switch. Since the magnetic switch 74 is interconnected with the rest of the electrical and electronic system, the activation of this switch now closes the solenoid valves 68 so that the cylinder 30 is maintained in the position it occupies at this moment. And at the same time the magnetic switch activates the solenoid valve 70' so that hydraulic fluid is directed through the line 66 into the cylinder 24 and against the rear portion of the piston contained therein. The pressure thus applied against the rear portion of this piston forces the piston to its innermost position within the cylinder 24, and pulls a portion of the lifting rod 26 into the cylinder 24 also. Thus, the effective shortening of the rod 26 is transmitted to the lid through the lid arm 28 through the upper swivel bearing 22. The lid is now forced to swing upwardly and open upon the sliding hinges 56. When the lid reaches its openmost position, the electronic system operates upon the solenoid valve 70 to close the valve and maintain the lid in this position. When the operator is ready to close the lid, he presses the close button on the electric switch 72, and the operation of this switch is transmitted to the electronic system so that the reverse operation begins. Initially the solenoid valve 70 is activated so that the pressure is released from the rear portion of the piston within cylinder 24, and the hydraulic fluid is now pumped to the face of the piston within cylinder 24 and the piston begins its travel to the other extremity of the cylinder. In turn, the rod 26 emerges further from the cylinder 24 and again acting through the lid arm 28 and the upper swivel bearing 22 forces the lid 14 to swing downwardly upon the hinges 56. As the lid reaches its closed position, the magnetic switch 74 is again activated. The switch 74, acting through the interconnected electronic system, causes the solenoid valve 70 to release the hydraulic pres= sure from the cylinder 24 and causes the solenoid valve 68 to operate so that the hydraulic fluid is directed to the rear portion of the piston located within cylinder 30. The pressure upon the rear of the piston within cylinder 30 is transmitted again through the plunger 32 and sleeve 34 and guide pin 36 to the flange 42 so that the lid 14 is now rotated in a clockwise manner until the locking pins 64 are forced securely against the locking flanges 62. After this position is reached the solenoid valves are automatically positioned so that all hydraulic pressure is relaxed and the pump is automatically turned off.

Since many different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the specific embodiment described in detail herein is not to be taken in a limiting sense since the scope of the invention is best defined by the appended claims.

What is claimed:

1. A canning retort comprising, in combination:

an upright tubular body closed at the lower end thereof and having an open upper end;

a lid pivotally attached to said tubular body to cover said open upper end;

hinge means affixed to said tubular body adjacent said open upper end and aflixed to the periphery of said lid whereby said lid is pivotable about said hinge means in substantially a vertical plane and rotatable about said hinge means through a horizontal arc;

hydraulic means for pivoting said lid in the vertical plane to fully expose the upper open end of said tubular body;

a plurality of spaced locking arms aflixed at the periphery of the upper open end of said tubular body, each locking arm having a substantially horizontally extending portion;

a plurality of spaced substantially radially extending pins aflixed to the upper peripheral surface of said lid, one of said locking pins positioned adjacent each of said locking arms whereby, when said lid is in the closed position, said lid may be rotated to move said locking pins beneath said horizontally extending portions of said locking arms; and

hydraulic means of rotating said lid,

2. A canning retort as described in claim 1 wherein said hydraulic means of rotating said lid comprises a hydraulic cylinder attached by one end to said tubular 'body, said cylinder having a piston rod extending therefrom, a sleeve secured to the outer end of said piston rod and a pin attached to said sleeve wherein said pin fits removably into an opening of a horizontally extending peripheral flange portion of said lid when said lid is in a closed position.

References Cited by the Examiner UNITED STATES PATENTS THERON E. CONDON, Primary Examiner. G. T. HALL, Assistant Examiner. 

1. A CANNING RETORT COMPRISING, IN COMBINATION: AN UPRIGHT TUBULAR BODY CLOSED AT THE LOWER END THEREOF AND HAVING AN OPEN UPPER END; A LID PIVOTALLY ATTACHED TO SAID TUBULAR BODY TO COVER SAID OPEN UPPER END; HINGE MEANS AFFIXED TO SAID TUBULAR BODY ADJACENT SAID OPEN UPPER END AND AFFIXED TO THE PERIPHERY OF SAID LID WHEREBY SAID LID IS PIVOTABLE ABOUT SAID HINGE MEANS IN SUBSTANTIALLY A VERTICAL PLANE AND ROTATABLE ABOUT SAID HINGE MEANS THROUGH A HORIZONTAL ARC; HYDRAULIC MEANS FOR PIVOTING SAID LID IN THE VERTICAL PLANE TO FULLY EXPOSE THE UPPER OPEN END OF SAID TUBULAR BODY; A PLURALITY OF SPACED LOCKING ARMS AFFIXED AT THE PERIPHERY OF THE UPPER OPEN END OF SAID TUBULAR BODY, EACH LOCKING ARM HAVING A SUBSTANTIALLY HORIZONTALLY EXTENDING PORTION; 